1. Field
The exemplary embodiments relate to a display apparatus. More particularly, the exemplary embodiments relate to a display apparatus which can perform recording through a touch on a screen.
2. Description of the Related Art
Demand for a display device, which can perform recording, such as writing on a screen or drawing a picture, by having a touch device (e.g., electronic pen or user's finger) touch the screen, has been increased, and a representative example of such a display device may be an electronic board.
In such a display device, in order to specify a recording point on a screen, it is necessary to sense the position of a touch device. In order to sense the position of the touch device, for example, there is a scheme for a touch sensor which includes a plurality of LEDs arranged along an edge region of a screen to emit infrared rays along the screen and a plurality of phototransistors arranged to face the plurality of LEDs to sense the infrared rays emitted from the plurality of LEDs, and senses the touch position based on the change of a reception amount of infrared rays in the phototransistors depending on whether the touch device approaches or recedes from the screen.
According to this touch sensing scheme, in the case where not only the touch device comes in contact with the screen but also the touch device, which does not come in contact with the screen, enters into a space on the screen on which infrared rays are scanned, the touch device acts as an obstacle against the infrared rays and thus it is sensed that the screen is touched by the touch device.
Due to such a touch sensing error, unintended noisy portions may be displayed on the screen together with intended portions on which a user intends to perform recording, and this may result in deterioration of the performance of the display device.